It is a no, for many reasons.
If you're taking lithium, I would guess it is for a psychiatric problem. In which case, you shouldn't be messing around with mind altering, psychedelic substances.
Let your medicine work and don't take the chance of causing yourself more harm. (I'm not trying to be condescending at all).
There's a few reasons there are warnings with LSD + Lithium
Seizures being top of the list.
It may reduce your trip significantlly, making it impossible to have any form of experience.
It may make you trip, but in a more dissociative way, which would be foul.
All in all, just don't mix them. This is just a very limited bit of information why you shouldn't, I'm sure others will add more.
A simple google search will show you, it just isn't a good idea.